Scale remover for tubes



Feb. 28, 1928.

C. R. ARCUS SCALE REMOVER FOR TUBES Filed Pee. 2. 1926 C w w e Z H 0 e t vmo m 5 Patented F eb. 28, 1928.

. tee-0,406

UNITED STATES PATENT OFFICE.

CHARLES ROBERT ARCUS, OF BAMSGATE, ENGLAND; ASGIGNOR TO CLAXTON AND CO]![- PANY LIMITED, OF RAIVISGATE, ENGLAND.

SCALE REMOVEB FOR TUBES.

Application filed December 2, 1926, Seriai No. 152,234, and inGreat Britain December 10, 1 925.

This invention relates to improved means forremoving scale from boiler tubes and the like and has for its object to enable a-n'e'fficient' method of removing scale from the tubes to be put into practice by means of simple "apparatus adapted to be traversed through the tubes so as to' apply heat thereto locally in such a Jmanner that the heated scale on the tube will dry and crack off in loose particles, which maybe readily removed.

Heretofore it has been proposed to provide heating means adapted to be passed along the tubes and to be traversed along their length in such afnianner that the heat will'be applied locally to the tube as the device is traversed along the length thereof. For this purpose, the heating means heretofore proposed comprises in one instance an oxygen burner, and in another instance a burner to which pipes are connected, one of which conveys air or oxygen and-the others conveying acetylene or oil vapour'to a com' mon mixingchamber. The combustion takes place inside the boiler tube -it'self,'but as the carbon or incrustation is averypoor conductor of heat, the metal boiler tube is liable to get excessively heated. In one heretofore proposed device,v it is proposed to obviate this by directing a'cooling liquid from the burner into the boiler tube subsequent to each heating operation. According to m invention the combustion of the fueldoes not take place ins'ide the boiler, tube itself, but inside a shell which is fed along the interior of the boiler tube, the shell having openings to allow flames to issue from the shell and spread around the interior of the boiler tube; p n In carrying my invention into practice, I prefer to employ a burner mounted upon the endof a suitableshaft as heretofore proposed,.the shaft being of a sufficient length to enable the burner to betraversed throughout the whole length of. the tubes to be treated. i

A convenient construction of burner for use with liquid fuel comprises a; suitable there is apipe for thefuel parallel with it which'is led through holes drilled or other- 1' w se Iormed n the burnerhead to one end of a vaporizing 0011. This coil may convenientlyconsist of a suitable length of pipe or casting of any suitable metal, one end of which is attached to the hole leading to the fuel supply passage in the'hollow shaft. The

central nozzle'at theend of the head soarranged as to direct the vap ourize'd fuel toward the vaporizing coil. The fuel issuing from the nozzle is ignited in the usual way so that the flame will maintainithe vaporiz other end is secured tothe burner head and" leads' into" a passage communicating with a.

other tube into which the device isfinserte'd so as to play upon the interior offthe tube and effectively heat it so as to cause any scale thereon to dry up and crack off in loose particles as the burner is traversed along the length of the tube. A suitable casing of tubular or other desii'edform may bePmOuntedround the burner head and the vaporizing coil and a suitable outlet and deflector may be arranged upon the end of this casing so as to direct theflame outwardly againstthe surface of the tubes in which the device is used. For this purposetan end plate may y be provided on the casing formed with curved r inclined vanes or deflectors adaptf ed to impart. swirl ng motion to the gases to assistin mixing the vaporized fuel and air and to direct'theburning mixture out wardly againstithe surface of the tube under treatment. i

' Suitable" apertures be provided through the burner head to permit an ample supply of air to ensure correct combustion. f

Forthispurpose the burner headmaybe formed w th an apertured flange or a numher of radial arms connected .to the sides i of the tubular casing thus leaving ample openings for the passageof'air to the burner. The tubular casingon the burneris arranged to be 'a' loose easy fit in the tubes under treatment and thusacts as a gllldelll passing through the tubesy' q I In order that this invention may be clearly understood andreadily carried into e'fie ct,

I have appended hereto a sheet of. drawings ficiently long to enable the burner to be.

traversed a'longthe length of a boiler tube, and for this purpose the shaft Z) may be constituted by" a number of rodsor shafts.

detach'ably connected in series endv on end. The burner a is in the form ofia part cylindrical head having a passage 0 for liq uid fuel; such passage to having. connected to one end" of it a tube dconnected to a source of'li uidflfuelsupply by a pipe 6 which runs parallel with the shaft Z), and the shaft 1 employed for conveying liquid fuel to the tubed. The other en'd'of the passage 0 communicat'es withl-a'jet fpreferably disposed upon the axis of a cylindrical casing 9, accommodating theburner; a and the tube d. The tubedpreferably is formed with a coil h located across the path of the flame issuing.

from the jet 7, wherebythe liquid. fuel in the tube 01' can become atomized or vapourized. l r

The casing g is a cylindrical metal shell open at its inner end or base 2'; but provided witha cap jiat' its outer or upper end. The

cap y'is provided with openings for the emission of the burning combustible mixture, and these openings arepreferably arranged so that the flame and hot gases issuein aspreading or fan-like manner from the cap This can be efiected by making the. said openings in the form of a numberof substantially radiatingslots la, the intermediate blades Z each being flared outwards, so that one radial'edge is above the other radial edge, the inner ends of the blades being turned in a substantially tangential direction. By this means the issuingfl'ames and-hotgases will tend totravel in a spirallikemanner along the tube being treated. The shaft 7) is provided with anyaperture flange and number of radial armsm the CPS- riphery or. outer ends of-which is, or -are,,secured'to the shell'g. If desired one sideof v the shell 9 may be formed with an opening as indicated at ,n, or a number of openings may be provided. The outer or upper end of the shell 9 is also preferably provided with a-number of openings 0 through which flames deflected by the. coil It may pass and impinge radially uponthe boiler tube.

The operation ofcleaning boiler tubesaccording to my invention is carried out with the boiler empty. The device is passed slowly along the length of each tube in turn so that the tube issubjected to a sufliciently high temperature to heat the scale on the tube causing. it to crack 011' in flakes which. will fall to the bottom of the boiler and may be easily removed through the usual manhole or slud'gefoutlets. The local application of heat to thetube causes it to expand cient than the usual methodloi scraping off? the scalefr-om between the tubes andenahles the whole of the scale to be removed,th1i s promoting. .econom J of" fuel'vandzyensuring greater efficiency. o the boiler iniuse Whenit is desired to withdraw tubes from the boiler, thisc n be .gr tlyiacilita d by first removing scale in the manner described.

1. A scale remover forboiler. tubes com.- prising a cylindrical, shelliiminovablI fixed on an axial manipulating shaft..wh1cli'.exe tends into the shell from the rear. end thereof, a fixedhead on the inner end. of" said shaft aburner'on said fixedhead', a. fuel conveying pipe" to said hurner whichextends alongside and parallel with the shaft, and a front. endwall'. to the shelllhawing a plu= may of apertures .to divide the flame .emerg; ing from the. burner. into av number of separate flame tongues. y

2;.A scale remover for boilerjtubes com prising in c mbin ti n, a liqu df el' urn r,

a cylindrical shell'i-n which burner is housed,.having a front end face in a plane perpendicular to the axis of-said shel1,. a

number of openingswin such end. face nadial ing a front end face ina plane perpendicular to the; axis. of said qsh'ell a number .of

openings in such end face, and outwardly fi'aredfblades between the said openings .to

spread in spiral fashion tongues of flame which emerge from the openings. 7 y

41. A scale remover for boiler tubes com prising innombinatloma l quid fuel burner,

a shell in which said burner is housed, hav

at its inner end in which the burner is mounted, a liquid fuel conveying pipe disposed alongside the shaft, parallel therewith, and

having an extension locatedwithin the shell between the burner and the front end of the shell and connected to a liquid fuel passage in the shaft head, and an apertured flange positioned between the shaft head and the rear end of the shell, by which the shell is secured to the shaft.

CHARLES ROBERT ARoUs. 

